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| author | Alexey Gladkov <legion@kernel.org> | 2021-04-22 15:27:16 +0300 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2021-04-30 22:14:03 +0300 |
| commit | c1ada3dc7219b02b3467aa906c2f5f8b098578d1 (patch) | |
| tree | ed42c25748ccbec5d4704b99d4934f1b6c91ffe8 /include/linux/user_namespace.h | |
| parent | e4aebf06695c32d49f1007f9d252f97b5b2998a7 (diff) | |
| download | linux-c1ada3dc7219b02b3467aa906c2f5f8b098578d1.tar.xz | |
ucounts: Set ucount_max to the largest positive value the type can hold
The ns->ucount_max[] is signed long which is less than the rlimit size.
We have to protect ucount_max[] from overflow and only use the largest
value that we can hold.
On 32bit using "long" instead of "unsigned long" to hold the counts has
the downside that RLIMIT_MSGQUEUE and RLIMIT_MEMLOCK are limited to 2GiB
instead of 4GiB. I don't think anyone cares but it should be mentioned
in case someone does.
The RLIMIT_NPROC and RLIMIT_SIGPENDING used atomic_t so their maximum
hasn't changed.
Signed-off-by: Alexey Gladkov <legion@kernel.org>
Link: https://lkml.kernel.org/r/1825a5dfa18bc5a570e79feb05e2bd07fd57e7e3.1619094428.git.legion@kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Diffstat (limited to 'include/linux/user_namespace.h')
| -rw-r--r-- | include/linux/user_namespace.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h index 2a3177b9b8bf..61794ae32fa8 100644 --- a/include/linux/user_namespace.h +++ b/include/linux/user_namespace.h @@ -125,6 +125,12 @@ long inc_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v); bool dec_rlimit_ucounts(struct ucounts *ucounts, enum ucount_type type, long v); bool is_ucounts_overlimit(struct ucounts *ucounts, enum ucount_type type, unsigned long max); +static inline void set_rlimit_ucount_max(struct user_namespace *ns, + enum ucount_type type, unsigned long max) +{ + ns->ucount_max[type] = max <= LONG_MAX ? max : LONG_MAX; +} + #ifdef CONFIG_USER_NS static inline struct user_namespace *get_user_ns(struct user_namespace *ns) |